Increasing capacitance of a capacitor

Abstract

A chemical etch is performed on a sheet of material. An electrochemical etch is performed on the sheet of material after the chemical etch is performed on the sheet of material. A capacitor is fabricated such that an electrode included in the capacitor includes material from the sheet of material after the electrochemical etch was performed on the sheet of material. In some instances, the chemical etch included at least partially immersing the sheet of material in an etch bath that includes molybdenum. Additionally or alternately, the chemical etch can be performed for a period of time less than 60 s.

The invention claimed is: 
     
       1. A method fabricating a capacitor by increasing a surface area of a sheet of material, comprising:
 performing a chemical etch on the sheet of material, wherein the chemical etch includes immersing the sheet of material in a chemical etch bath, the chemical etch bath includes molybdenum and has a pH greater than 0.0 and less than or equal to 2.5; 
 performing an electrochemical etch on the sheet of material after performing the chemical etch on the sheet of material, wherein the electrochemical etch including immersing the sheet of material in an electrochemical etch bath, the electrochemical etch bath includes molybdenum and has a pH greater than 0.0 and less than or equal to 2.5; and 
 extracting an electrode from the sheet of material after performing the electrochemical etch on the sheet of material. 
 
     
     
       2. The method of  claim 1 , wherein the chemical etch is performed for less than 45 seconds. 
     
     
       3. The method of  claim 1 , wherein the chemical etch is performed for a time period between 0 seconds and 20 seconds. 
     
     
       4. The method of  claim 1 , wherein the molybdenum included in the chemical etch bath is in element form or is included in a compound. 
     
     
       5. The method of  claim 4 , wherein the molybdenum is included in a chemical component selected from the group consisting of molybdic acid, molybdenum trioxide, sodium molybdate dihydrate, molybdenum (V) chloride, molybdenum sulfide, molybdenum (IV) dioxide, and molybdenum (II) chloride. 
     
     
       6. The method of  claim 1 , wherein the molybdenum included in the electrochemical etch bath is in elemental form or is included in a compound. 
     
     
       7. The method of  claim 6 , wherein the molybdenum is included in a chemical component selected from the group consisting of molybdic acid, molybdenum trioxide, sodium molybdate dihydrate, molybdenum (V) chloride, molybdenum sulfide, molybdenum (IV) dioxide, and molybdenum (II) chloride. 
     
     
       8. The method of  claim 1 , wherein the chemical etch includes immersing at least a portion of the sheet of material in an etch bath and the electrochemical etch includes immersing at least a portion of the sheet of material in the same etch bath. 
     
     
       9. The method of  claim 8 , wherein the sheet of material is not removed from the etch bath between the chemical etch and the electrochemical etch. 
     
     
       10. The method of  claim 9 , wherein an electrical potential is not applied across the sheet of material during the chemical etch but is applied during the electrochemical etch or an electrical potential applied across the sheet of material during the chemical etch is less than 5% of the electrical potential applied across the sheet of material during the electrochemical etch. 
     
     
       11. The method of  claim 9 , wherein an electrical current is not passed through the sheet of material during the chemical etch but does flow through the sheet of material during the electrochemical etch or an electrical current is passed through the sheet of material during the chemical etch at less than 5% of an electrical current passed through the sheet of material during the electrochemical etch. 
     
     
       12. The method of  claim 9 , wherein the chemical etch is performed for less than 45 seconds. 
     
     
       13. The method of  claim 12 , wherein the chemical etch is performed for a time period between 0 seconds and 15 second.